Foam breaker



Dec. 6, 1949 H. w. DENHARD FOAM BREAKER Filed Dec. 29, 1945 w H I M4 M mM? mm W p H B M, E. a m I. FHQEE E w u M 1C a 1 a 5 l l L/QUOE OUTLETPatented Dec. 6, 1949 FOAM BREAKER Harry W. Denhard, Sebastopol, Calif.,assignor to Oliver United Filters Incorporated, Oakland, Calif., acorporation of Nevada Application December 29, 1945, Serial No. 637,901

6 Claims. (Cl. 252-361) This invention relates to a device for breakingdown the foam incidently formed in many industrialoper'ations as theresult of pumping or otherwise agitating a soapy fluid in the presenceof air.

The problem of eliminating foam of this character is one of longstanding and many expedients have been resorted to in an attempt tosolve it. For example, various chemical reagents with the thought ofdecreasing the surface tension of the bubbles; flames have been appliedwith the hope of expanding the bubbles to a point where their collapsewill take place; and various mechanical devices have been tried whereinthe foam is made to pass through a screen or restricted zone on thetheory that in so doing the bubbles will collapse. It has been found,however, that for one reason or another all of these methods have beenineffective. In the case of the devices employing a screen or restrictedpassageway the bubbles simply reform on emerging from the screen orpassageway.

In general the object of this invention is the provision of a mechanicalfoam breaker wherein the foam is delivered to the interior of acentrifugal basket formed with solid walls, the foam being broken by thecentrifugal pressure imposed thereon.

The invention possesses other advantageous features, some of which withthe foregoing will be set forth at length in the following descriptionwhere that form of the invention which has been selected forillustration in the drawings accompanying and forming a part of thepresent specification is outlined in full. In said drawings, one form ofthe invention is shown, but it is to be understood that it is notlimited to such form, since the invention as set forth in the claims maybe embodied in a plurality of forms.

The single figure of the accompanying drawing is a vertical mid-sectionof a foam breaker embodying the objects of my invention.

The device thereon shown comprises a cylindrical housing or shell I,provided at its lower end with an outwardly extending flange 2 forbolting it to a foam delivery conduit 3, and at its upper end with aninwardly extending flange 4 for bolting it to an upwardly dished cover5. Provided on the shell adjacent the lower flange 2 is a threadedliquor outlet connection 6, and formed on the cover -5 is a flanged airdischarge connection 1.

Formed centrally of the cover 5 is a depending hub 8 provided on itsupper and lower ends respectively with ball bearings 9 and l I.

Bolted to the cover 5 concentrically with the shell I is a motor I2,having a drive shaft 13 terminating in a coupling I4. Engaging thecoupling I4 is a coupling I5 carried on the upper end of a shaft Hi, theshaft It being journaled at its upper end in the ball bearing 9. Keyedto the shaft [6 is a sleeve I1 journaled in the bearing H, and welded tothe sleeve I1 is a spider l8 provided with a ring [9. Riveted to thering i9 by an inwardly extending flange 2| is a downwardly divergingsolid Walled centrifugal basket 22 formed at its lower end with a bead23 in horizontal alignment with the liquor outlet connection 6.

Welded to the basket 22 are a plurality of peripherally spaced,vertically extending vanes 24, terminating at their lower endsimmediately above a downwardly and inwardly extending flange 25 formedintegral with the shell I.

In the operation of the device above described, foam passing upwardlythrough the conduit 3 is delivered to the inner walls of the centrifugalbasket 22 and rotates therewith at from 1200 to 1500 R. P. M. Thecentrifugal force so produced collapses the foam bubbles against thewalls of the baskets, the resulting liquor traveling downwardly over itsdiverging walls and around its head 23. The liquor is then thrown fromthe bead 23 into the lower end of the shell I from which it can be drawnoff through the connection 8. Simultaneously the vanes 24 serve as animpeller to force the air content of the collapsed foam upwardly throughthe shell I and out through the connection 1.

Although my foam breaker has been particularly designed for installationin a kraft black liquor washing system, its use is by no means limitedto this type of system.

I claim:

1. A foam breaker comprising: a solid walled downwardly divergingcentrifugal basket having an unobstructed open lower end arranged toreceive a foam delivery duct therein; means for delivering foam to apoint within said basket adjacent the walls thereof; and a shellsurrounding said basket adjacent its rim; the interior of saidcentrifugal basket being substantially unobstructed, the inclination ofthe walls of said basket with respect to its axis being substantiallyless than 20.

2. A foam breaker comprising: a downwardly diverging solid walledcentrifugal basket having an unostructed open lower end arranged toreceive a foam delivery duct therein; a shell surrounding said basket inspaced relation thereto;

peripherally spaced, longitudinally extending vanes secured to the outersurface of said basket; said shell being provided with an air dischargeoutlet at its upper end and with a liquor discharge opening at its lowerend; the interior of said centrifugal basket being substantiallyunobstructed.

3. A foam breaker'comprisin-g: .a downwardly diverging'solid walledmotor driven centrifugal basket; having an unobstructed open lower endarranged to receive a foam delivery duct therein; a plurality oflongitudinally extending, peripherally spaced vanes mounted on the outersurface of said basket, the lower ends of said vanes terminating at apoint substantially above the,

lower end of said basket; a shell surrounding said basket and providedwith. an inwardly and downwardly extending fian'geadjacent and below thelower ends of said vanes, saidshell being provided at its upper end withan air outlet and at its lower end with a liquor outlet; the interior ofsaid centrifugal basket being substantially unobstructed.

4. A foam breaker comprising: .a cylindrical shell havingan open lowerend and closed at its upper end by a cover; -a shaft journaled in saidcover coaxially with said shell; a motor mounted on said coverin drivingengagement with said shaft; a downwardly diverging solid walledcentrifugal basket carried by said shaftfor-rotation therewith andhaving an unobstructed. open lower end arranged to receive a foamdelivery duct therein; and longitudinally extending peripherally spacedvanes mounted on the outer surface of said basket said shell beingprovided with an inwardly and downwardly converging skirt extending.below thelower ends of said vanes to a point adjacent said basket; thein- 1 Lbasket for delivering foam thereinto adjacent .the walls thereof;and a shell surrounding said "basket adjacent its rim.

-6. A foam breaker comprising: a solid walled 'idownwardly divergingcentrifugal basket having anopen-lower end and containing no vanes orother obstructionswithin its confines, the inclination of the walls ofsaid basket with respect to; its axis being substantially less than 20";a shell surrounding said basket; and means for rotatably mounting saidbasket within said shell.

HARRY W; DENHARD.

REFERENCES CIT ED ,-The following references are of record in the fileof this patent:

UNITED STATES PATENTS Name Date Jantzen .July 24, 1934 Edwards June4,1946 Naucler Aug. 10, 1948 FOREIGN PATENTS Country Date NetherlandsFeb. 15, 1926 Number Number

